Assembly consisting of a complex transparency device and at least one array of micro-images, as well as a security document comprising same

Abstract

An assembly comprising a complex transparency device, i.e. a refractive and/or diffractive device acting on the light phase, and at least one array of micro-images, wherein: the complex transparency device comprises a periodical two-dimensional array formed from individual “pupils,” wherein each pupil comprises a micro-optical device, at least some of the micro-optical devices having a non-centered optical axis, and at least some of the micro-optical devices positioned non-periodically with variable off-setting of the optical axis thereof with the array; the array of micro-images comprising as many micro-images as micro-optical devices; each micro-image has a contour identical to that of the associated pupil and a surface which is at the most identical to that of the associate pupil; and each micro-image is sub-divided into at least one thumbnail image such that when the transparency device is positioned facing the array of micro-images, and an observer observes the array through the transparency device, the observer sees, at least in a given direction of observation, an image which is reconstructed by the combination of the thumbnail images associated with the direction, wherein within the same subdivision, certain thumbnail images, form “firsts group” and are distributed such that when the transparency device is positioned facing the array of micro-images, the thumb-nail images are respectively arranged according to the optical axis of the associated micro-optical device.

The invention claimed is: 
     
       1. An assembly comprising:
 a complex transparency device having a refractive or diffractive device acting on the phase of the light and at least one micro-image array, wherein: 
 said complex transparency device consists of a periodic two-dimensional array formed of individual pupils in which each pupil includes a micro-optical device, wherein at least a part of the micro-optical devices have a non-centered optical axis and at least a part of the micro-optical devices are positioned non-periodically; wherein at least two different non-centered optical axes of at least two different micro-optical devices within said array have different positions within their respective pupils; 
 the at least one micro-image array comprising as many micro-images as there are micro-optical devices; 
 each micro-image has a contour identical to that of the associated pupil and a surface identical to that of the associated pupil;
 each micro-image is subdivided into one or more thumbnail images, so that when said transparency device is positioned facing said micro-image array and said array is observed through said transparency device, an image reconstructed by the combination of the one or more thumbnail images associated is observable at least along a given direction of observation, and 
 wherein within the one or more thumbnail images, a first group of thumbnail images is distributed in such a way that when said transparency device is positioned facing said micro-image array, each thumbnail image of the first group of thumbnail images is disposed along the optical axis of an associated micro-optical device. 
 
 
     
     
       2. The assembly according to  claim 1 , wherein each of the micro-optical devices include a non-centered optical axis and all the micro-optical devices are positioned non-periodically. 
     
     
       3. The assembly according to  claim 1 , wherein said pupils are of identical shape and surface. 
     
     
       4. The assembly according to  claim 1 , wherein the micro-optical devices having a non-centered optical axis consist of Fresnel lenses. 
     
     
       5. The assembly according to  claim 1 , wherein said micro-optical devices having a non-centered optical axis consist of circular blazed gratings. 
     
     
       6. The assembly according to  claim 1 , wherein each micro-image is subdivided into at least two thumbnail images. 
     
     
       7. The assembly according to  claim 1 , wherein within the same subdivision a second group of thumbnail images is distributed in such a way that when said transparency device is positioned facing said micro-image array, each thumbnail image of the second group of thumbnail images are each disposed along the same axis, different from the optical axis of said associated micro-optical device. 
     
     
       8. The assembly according to  claim 1 , wherein the image reconstructed by the combination of the one or more thumbnail images of each subdivision, seen from at least one predetermined angle of observation, constitutes a recognizable information or has a recognizable visual effect. 
     
     
       9. The assembly according to  claim 8 , wherein said two-dimensional micro-image array is generated by a display device, whether it is mobile or not. 
     
     
       10. The assembly according to  claim 9 , wherein the display device is a digital tool screen. 
     
     
       11. The assembly according to  claim 1 , wherein said complex transparency device and said micro-image array are carried by the same medium. 
     
     
       12. The assembly according to  claim 1 , wherein said complex transparency device and said micro-image array are carried by different media. 
     
     
       13. An apparatus, comprising:
 a first face and a second face opposite the first face, wherein at least one of the first face or second face carries a complex transparency device includes:
 a periodic two-dimensional array formed of individual pupils in which each pupil includes a micro-optical device, wherein at least part of the micro-optical devices have a non-centered optical axis and at least a part of the micro-optical devices are positioned non-periodically; wherein at least two different non-centered optical axes of at least two different micro-optical devices within said array have different positions within their respective pupils; 
 wherein each micro-image array comprising as many micro-images as there are micro-optical devices, 
 wherein each micro-image has a contour identical to that of the associated pupil and a surface identical to that of the associated pupil, 
 wherein each micro-image is subdivided into one or more thumbnail images, so that when said transparency device is positioned facing said micro-image array and said array is observed through said transparency device, an image reconstructed by the combination of the one or more thumbnail images associated is observable at least along a given direction of observation, and 
 wherein within the one or more thumbnail images, a first group of thumbnail images is distributed in such a way that when said transparency device is positioned facing said micro-image array, each thumbnail image of the first group of thumbnail images is disposed along the optical axis of an associated micro-optical device. 
 
 
     
     
       14. The apparatus according to  claim 13 , wherein the complex transparency device extends above a printing carried by the first or second face, this printing constituting the two-dimensional micro-image array. 
     
     
       15. The apparatus according to  claim 14 , wherein said printing consists of at least one ink chosen from the group consisting of the following inks: visible black ink, colored ink, matt ink, gloss ink, ink with iridescent effect, metallic ink, optically variable ink, invisible ink but visible under ultraviolet radiation (fluorescence or phosphorescence) or visible under infrared radiation. 
     
     
       16. The apparatus according to  claim 13 , wherein the complex transparency device extends through a window which opens on said opposite faces, and
 wherein the complex transparency device further includes a printing constituting the two-dimensional micro-image array disposed relative to each other so that they can be superimposed at least momentarily. 
 
     
     
       17. The apparatus according to  claim 13 , wherein said printing consists of at least one ink chosen from the group consisting of the following inks: visible black ink, colored ink, matt ink, gloss ink, ink with iridescent effect, metallic ink, optically variable ink, invisible ink but visible under ultraviolet radiation (fluorescence or phosphorescence) or visible under infrared radiation. 
     
     
       18. The apparatus according to  claim 13 , wherein the complex transparency device is coated with a layer of transparent varnish, so that the upper surface of said device is planar. 
     
     
       19. The apparatus according to  claim 13 , wherein the apparatus is a security document. 
     
     
       20. The apparatus according to  claim 19 , wherein the security document is a bank note.